Implement lxc network setup script

This script prepares bridge for lxc containers.

1 files changed, 40 insertions, 0 deletions

diff --git a/local/bin/lxc-net b/local/bin/lxc-net
new file mode 100755
index 0000000..d7e4a17
--- /dev/null
+++ b/local/bin/lxc-net
@@ -0,0 +1,40 @@
+#!/bin/sh
+
+if [ "$(id -u)" -ne 0 ]; then
+	echo "Root required for execution" >&2
+	exit 1
+fi
+
+# What if we want to clean
+if [ "$1" = "clean" ]; then
+	kill $(cat /tmp/lxc-dhcpd.pid)
+	rm -f /tmp/lxc-dhcpd.pid /tmp/lxc-dhcpd.conf
+	ip link del name vbr0
+fi
+
+# Setup bridge
+ip link add name vbr0 type bridge
+ip link set vbr0 up
+ip addr add 192.168.30.1/24 dev vbr0
+
+# Start dhcp server
+
+# This just takes first dns nameserver configured. Maybe we might want to be
+# little bit more clever.
+DNS_SERVER=$(cat /etc/resolv.conf |grep -i nameserver|head -n1|cut -d ' ' -f2)
+echo "# DHCPD configuration generated by lxc-net script
+authoritative;
+default-lease-time 600;
+max-lease-time 7200;
+option subnet-mask 255.255.255.0;
+option broadcast-address 192.168.30.255;
+option routers 192.168.30.1;
+option domain-name-servers $DNS_SERVER;
+subnet 192.168.30.0 netmask 255.255.255.0 {
+   range 192.168.30.10 192.168.30.100;
+}" > /tmp/lxc-dhcpd.conf
+dhcpd -4 -pf /tmp/lxc-dhcpd.pid -cf /tmp/lxc-dhcpd.conf vbr0
+
+# Setup network forwarding (TODO add -o ethX to iptable command)
+sysctl  net.ipv4.ip_forward=1
+iptables -t nat -A POSTROUTING -j MASQUERADE